Instead of using homemade sprays, gardeners should develop pest management plans, Virginia Tech expert says
Gardeners should be wary of homemade cure-all pesticide recipes and instead monitor their gardens, identify the pests they have, and develop an integrated pest management plan for their plants.
When Stephanie Blevins Wycoff, a consumer pesticide safety expert with Virginia Cooperative Extension, noticed damage on her tomato plants last spring, she didn’t reach for a pesticide. Instead, she began an investigation to find the culprit and determine what she should do to protect her plants.
“It turned out to be tomato hornworm, but by the time I found it, it had been parasitized by insect larvae and was no longer a threat,” said Blevins Wycoff.
As a Virginia Cooperative Extension scientist, Blevins Wycoff understands the important role all Virginians can play in protecting our commonwealth's environment and natural resrouces. Using pesticides safely, correctly, and only when necessary by developing an integrated pest management plan is one way we can advance the wellbeing of our environment and communities.
Home gardeners who identify frustrating and destructive garden pests might be tempted to turn to the internet where recipes for homemade pesticide sprays have proliferated in recent years. Although they may be touted as cure-alls, mixtures made from household ingredients like dish soap or vinegar have not been vetted for effectiveness or tested for potential environmental impacts. They can also damage plants by causing chemical burns.
“Before reaching for a chemical, we hope that people will try non-chemical control options first. That’s where integrated pest management comes into play,” Blevins Wycoff said.
Integrated pest management is a holistic, ecological approach to controlling pests. In this program, a gardener assesses plants to determine what the problem is, monitors for damage, determines at what threshold they need to take action, and attempts to prevent pest issues before implementing control methods, such as pesticides. With good planning, like encouraging beneficial insects or rotating crops to minimize disease, gardeners can also reduce the number of pest problems they encounter.
Gardeners interested in learning more about an integrated pest management program can read An Introduction to Integrated Pest Management or the 2022 Pest Management Guide for Home Grounds and Animals.
In many cases, pest or disease problems may also be controlled through non-chemical means, for example, by physically removing insects or diseased plant material. By identifying the pests and diseases they encounter in their gardens and monitoring carefully for signs of these problems, gardeners can stay on top of pests before they damage plants enough to reduce crop yields.
Although they can be annoying or unsightly, in some cases, pests or diseases may not cause enough damage to warrant intervention at all.
If gardeners do determine a pesticide is necessary, Blevins Wycoff recommends local Virginia Cooperative Extension offices as the best source of information for treatment. As trained experts and members of your community, Extension agents and Extension Master Gardener volunteers can help gardeners put scientific ideas into action as they identify pest problems, determine the best course of action, and if necessary, make a recommendation for a specific pesticide application based on the situation.
“Gardeners should be skeptical of anything that promises to be a cure-all,” Blevins Wycoff said. “If you’re applying something that promises to kill all insects, you might also be killing beneficial insects. If you have identified a specific pest, you can look for a registered that targets certain pests and will not harm other. ”
Registered pesticides have been tested and approved by the EPA and have information for application, efficacy, and first aid. There is a lot of infrastructure in place to ensure these products are safe and effective when used according to their labels. Extension agents and other trained pesticide safety educators can help gardeners determine if pesticides are appropriate and which they should use.
“Just because you find something on the internet, doesn’t mean it’s a good source of information,” Blevins Wycoff said. “Many times, you may not even need a pesticide to manage garden pests. You should always identify exactly what your problem is before taking action because you may discover that non-chemical control methods are effective.”
If you need assistance, your local Extension office can help. Find your local Extension office here.
Extension Master Gardeners are trained volunteer educators who work in communities across the commonwealth to share knowledge, implement research, and steward natural resources through research-based horticulture education. We bring the resources of Virginia’s land-grant universities to the people of the commonwealth. Contact your local Master Gardeners through your local Extension office or click here to learn more about gardening in Virginia and the Virginia Extension Master Gardener program.
- Written by Devon Johnson